- Process for the preparation of 1,1-dichloro-3,3,3-trifluoropropane
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A convenient and economical process for the preparation of 1,1-dichloro-3,3,3-trifluoropropane (HCFC-243) by the reaction of 1,1,1,3,3-pentachloropropane (HCC-240) with hydrogen fluoride in the presence of an activated hydrofluorination catalyst. Also, the selective fluorination of hydrochlorocarbons and/or hydrochlorofluorocarbons, or mixtures thereof is shown. A HCFC-243 reaction product yield of greater than 40% is obtained.
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Page/Page column 3
(2008/06/13)
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- Process of manufacturing 1,1,1,3,3-pentafluoropropane, process of manufacturing 2,2,3-trichloro 1,1,1,3,3-pentafluoropropane and process of manufacturing 2,3,3-trichloro-1,1,1-trifluoropropene
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2,2,3-trichloro-1,1,1,3,3-pentafluoropropane is used as a raw material, to which not less than 4.5 equivalent parts of hydrogen are added to effect a hydrogenation reaction in the presence of a noble metal catalyst, particularly a palladium catalyst, by the vapor phase method to manufacture 1,1,1,3,3-pentafluoropropane. Further, propane, propene, and hexachloropropene, etc. are chlorofluorinated in the presence of a metal catalyst to produce 2,2,3-trichloro-1,1,1,3,3-pentafluoropropane, then this compound is reduced with hydrogen in the presence of a noble metal catalyst to produce 1,1,1,3,3-pentafluoropropane. 2,2,3-trichloro-1,1,1,3,3-pentafluoropropane and 1,1,1,3,3-pentafluoropropane can thus be efficiently and economically produced.
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- HALOGEN EXCHANGE EQUILIBRIA OF CHLOROFLUOROOLEFINS
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The thermochemical properties of the following reactions were determined using either AlF3 or Cr2O3 as catalysts: (1) (2) (3) In addition, the cis-trans equilibria of both CF3CF=CFCl and CF3CCl=CFCl were able to be derived from the reaction data.The experimental thermochemical properties for reactions (1), (2) and (3) were compared with property values calculated using a well-known approximation method.A study of the exchange equilibria of chlorofluoroethylenes failed to yield accurate thermochemical values due to significant side reactions.However, a brief study of the mechanism of a catalytic disproportionation of CF2=CFCl: was carried out.
- Coulson, D. Robert
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- PHOTOCHEMICAL REDUCTION OF CARBON-HALOGEN BONDS. 3. REGIOSELECTIVITY OF THE REACTION IN FLUORINATED HALOGENOPROPANOATES.
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The ester group exhibits a strong directive effect in the photochemical reduction of a carbon-halogen bond and directs the reduction in perhalogenated chlorofluoropropanoates of the type CFXY-CClZ-COOR (X,Y,Z = Cl, F) to the α-position in the acyl part of an ester.The reduction takes place with the same regioselectivity even in esters CFCl2-CHCl-COOR (10).In esters containing an α -CCl2- group the reductions to the first and the second stages can be separated and the individual reduction products can be obtained preparatively.The α C-F bond is more difficult to reduce and therefore in the ester CFCl2-CHF-COOR (11) the β C-Cl bond was reduced specifically and in the ester CF2Cl-CHF-COOR (12) both the α C-F bond and the β C-Cl bond were reduced parallely.The relative reactivity of fluorinated halogenopropanoates with an α C-Cl bond showed only small differences in the reduction with 2-propanol in the presence of acetone as a sensitiser; the quantum yield Φ reached values of about 28-35 under kinetic measurements and thus proved the existence of a chain radical mechanism.
- Paleta, O.,Dadak, V.,Dedek, V.,Timpe, H.-J.
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p. 397 - 414
(2007/10/02)
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